Hello

Thanks for the query

Macrobid is Nitrofurantoin most commonly used to treat Biaxin is clarithromycin which is used in array of infection like pharyngitis, tonsilitis and less commonly in urinary tract infections.

There are no known drug interaction between them and if both are prescribed at the same time then it is most likely for either drug resistant infection or infections that require multiple drug regimen.

Common side effects of these drugs you might face are
1. Diarrhea
2.Nausea
3. Irritability (especially with clarithromycin )
4. Abdominal pain
5. Mild facial swelling

If any of these side effects are causing extreme discomfort or if you develop rashes, breathing difficulty then the drugs should be stopped immediately.

I hope I have answered your query, if there are no further queries please accept my answer

I wish you good health

Regards

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